Conservative Management for Equine Spinal Cord Compression
Equine Medical Treatment Options for Cervical Spinal Cord Compression
In some cases, there can be equine medical treatment and conservative management for the equine cervical spinal cord compression. Several equine medical treatment options include a change of activity level, osteoarthritic articular facet injections, young horse dietary management, and long-term anti-inflammatory therapy with NSAIDs and vitamin E. We have not had any direct experience with the benefit of alternative forms of therapy such as chiropractic manipulation or acupuncture.
There are a number of factors to consider in devising a conservative management approach for your horse with cervical cord compression. These include the accuracy of diagnosis, location of the cervical spinal cord compression, the degree of ataxia, insurance status, current occupation, and the owner's reasonable expectations.
ACCURACY OF DIAGNOSIS AND LOCATION OF LESION
Ideally, each patient will have had the diagnosis confirmed with a complete workup and especially a complete, diagnostic quality myelogram/CT. The other common causes of ataxia, such as EPM or EDM, will also have been ruled in or out. If the workup shows only mild compression (<grade 2/5) at C3/C4 or C4/C5 in flexion only and the patient is trying to be shown as a dressage horse, then a change in training, lowering expectations can produce a horse that is safe to ride on even safe surfaces. Avoiding the need or desire to have the cervical area in flexion reduces pressure on the cord.
The same lesions with more obvious clinical signs in a young racehorse candidate do not lend themselves to just a change in the intensity of training. If the patient is under a year of age, then a marked reduction in dietary supplementation (to slow the growth rate) and reduction of exercise (to reduce trauma to the cord) has been shown to result in athletes as two-year-olds.
Mild myelographic compression at C6/C7 in a horse that is currently being ridden without falling might respond to injections of the articular facets with corticosteroids if the myelogram shows the compression to be the result of synovial proliferation from an arthritic facet joint. If the compression at C6/C7 is due to a stenosis of the spinal canal, then the chances of any improvement from an articular facet injection are greatly reduced.
If the clinical signs are greater than Grade 3/5 and the compression at C5/C6 or C6/C7 is very obvious, then the chances of any response with medication, time, dietary change, and reduction in the amount of exercise are very poor. Breeding stallions can be managed with the use of NSAIDs, but mares in this category will have a difficult time conceiving (unless done by AI).
DEGREE OF ATAXIA
The degree of ataxia must be taken into account when advising the owners on treatment options. Patients that are greater than grade 3/5 can be at risk to themselves and should not be placed into situations that force them to contend with other horses, uneven and unsafe (muddy, frozen, or snowy) paddocks as they are prone to fall, and in the process injure themselves or spend countless hours unable to rise until discovered by their caretakers. They can also be at risk to their handlers as they can fall and injure the handler in the process or when the handler is trying to assist them to stand if they are recumbent. Patients in this category who have not been conditioned to handling and being led, feet picked up, and examined are more prone to resist pressure on a halter and respond by sudden backing and rearing – often falling on their head with resultant fractures of the skull.
Patients with a neurological grade less than 3/5 can be turned out in a paddock and may function well in a herd situation as long as they are with compatible horses. Patients who are less than a grade 3 and less than 2 years of age may show significant improvement if given a year or more for the cervical vertebra to remodel and reduce the compressive site. Patients over 2 years with a grade 2 or 3 ataxia do not have a good chance to respond.
Patients with signs less than grade 2 can respond if the work level (and Expectations) is significantly reduced. If the compressive lesion is a result of an enlarged facet and the patient is a large patient (C6/C7) who has been kept in a stall, then having more access to a paddock that allows them to lie down in an unrestricted position is most likely to improve.
INSURANCE STATUS
The guidelines for the treatment of cervical compressive lesions vary with insurance companies, types of policies, and the unique aspect of each patient/owner/veterinarian involved. Euthanasia does not seem to be a conservative treatment method, but if the patient is a grade 4 or 5 and the owners do not want to attempt surgical correction, then euthanasia is indicated, and most North American insurance companies would honor the claim. Many would do the same if 2 equine veterinarians graded the patient to a grade of 3/5 or more. Horses with an ataxia grade less than 3/5 may or may not have a claim honored.
EXPECTATIONS OF OWNER
The degree of improvement with conservative therapy depends a great deal on the clinical signs and the site and degree of cord compression. While anything is possible, it would be difficult for me to assure the owner that improvement over one grade would occur. For example, a 5-year-old lesion with a grade 2/5 and a single or double level compression in flexion only that was presented due to inability to perform even entry-level dressage is unlikely to progress to an entry-level with a regime of NSAIDs, vitamin E, dietary reduction and a 4 to 6 month rest period.
In fact, the most important aspect of conservative management is a reduction in the expectations of the owner.
If the owner is willing to change the occupation of the would-be dressage horse to that of a pleasure or trail horse that can be ridden with the cervical area in a neutral position, then the outcome may be more favorable.
Grade 2/5 patients do not usually become safe or useful trail horses as they do not enjoy going up or down hills, and many will develop personality traits trying to avoid this type of activity. They usually will not stumble or fall, but may do so if the trail is steep, has poor footing, and they are startled by unusual objects or movements on the trail. We try to discourage the use of Grade 2/5 patients for trail work. The owners should be warned of the potential safety problems, and young or inexperienced riders should not ride these horses.